Messaging systems can be used to implement substantially real-time asynchronous processing of events in a manner that is decoupled from processes that generate the events. To address various issues that arise with these systems, stream processing can be implemented on top of messaging systems as a higher-level layer of abstraction. For example, Apache Samza is one such stream processing framework that operates on streams of immutable messages of a similar type or category. These messages can be read from the streams by consumers, who can choose to take action in response to the messages. To date, existing stream processing systems have not yet reached maturity, resulting in the need to develop customized stream processing solutions to address the unique problems arising in certain large-scale data processors.